I was wondering if anyone knows where the Radiator fan switch is located on a 99-00 civic? Also, how easy is it to remove and install a new one?

 

If you are talking about the "thermoswitch" its located on the thermostat housing. Part of your wire harness will be plugged into it. Its really simple to take out. I just did a rad flush at the same time and drained my coolant, unplugged the connector and i believe i used a 22mm or 24mm closed end wrench. Its one of the two. Should take you about 1 minute to take out.

 

Thanks 95ProjectEJ1!!!